1. Field of Invention
The field of the present invention relates in general to wireless local area networks (WLAN) including wireless access points (WAP) and wireless stations and methods for optimizing links on same.
2. Description of the Related Art
Home and office networks, a.k.a. wireless local area networks (WLAN) are increasingly set up and serviced using a device called a Wireless Access Point (WAP). The WAP may include a router. The WAP couples all the devices of the home network, e.g. wireless stations such as: computers, printers, televisions, digital video (DVD) players and smoke detectors to one another and to the Cable or Subscriber Line through which Internet, video, and television is delivered to the home. Most WAPs implement the IEEE 802.11 standard which is a contention based standard for handling communications among multiple competing devices for a shared wireless communication medium on a single channel. Each home has a WAP which forms the center piece of the associated wireless networking between all the wireless enabled devices in the home, a.k.a. wireless stations or wireless network nodes. The WAP self-selects one of a number of frequency division multiplexed channels on which its network nodes or devices will communicate.
After selection of a single channel for the associated home network, the WAP controls access to the shared communication medium using a multiple access methodology identified as Carrier Sense Multiple Access (CSMA). CSMA is a distributed random access methodology first introduced for home wired networks such as Ethernet for sharing a single communication medium, by having a contending communication link back off and retry access to the line if a collision is detected, i.e. if the line is in use.
Communications on the single communication medium are identified as “Simplex” meaning, one communication stream from a single source node to one or more target nodes at one time, with all remaining nodes capable of “listening” to the subject transmission. To confirm arrival of each communication packet, the target node is required to send back an acknowledgment, a.k.a. “ACK” packet to the source. Absent the receipt of the ACK packet the source will retransmit the unacknowledged data until an acknowledgement is received, or a time-out is reached.
To improve the throughput on each point-to-point link between a WAP and a station, multiple antennas may be used. Devices with multiple antennas can exploit any of a number of techniques to increase link throughput specifically: a) controlling how data is loaded on to each antenna, b) how data is coded, and c) how the antennas signals are aimed at the receiving station. Typically, during an association phase the transmitting and receiving device identify their capabilities and agree on a compatible, i.e. common denominator, set of loading, coding and aiming options after which communications are initiated on the link.
What is needed is an improved method of operating a WLAN.